TABLE 1.

Overview of sdAbs used in the thrombosis and hemostasis field

Target protein	Camelid species/Synthetic library	sdAb nomenclature	Binding site	Activity	Application	References
Antithrombin	Llama	KB‐AT‐01 ‐ 07; KB‐AT‐23	None defined	Neutralization of antithrombin function	Research/Therapy	79
Factor VIIa	Llama	αFVIIa‐VHH	FVIIa protease domain	Detection of FVIIa but not FVII	Diagnostics	75
Factor VIIa	Llama	KB‐FVIIa‐004	FVIIa protease domain	Inhibits free FVIIa but not TF‐bound FVIIa activity	Research	49
Factor XIIa	Llama	A10	Catalytic domain	Binds selectively to α‐FXIIa	Research/Diagnostics	52
Factor XIIa	Llama	B7	Catalytic domain	Binds both α‐FXIIa and β‐FXIIa	Research/Diagnostics	52
Fibrinogen	Dromedary	VFIB1, ‐2, ‐3	None defined	High‐affinity binding to fibrinogen	Diagnostics	76, 77
PAI‐1	Alpaca	VHH‐s‐a98	Surface loops around central β‐sheet A	Switches PAI‐1/PA to substrate pathway	Research	105
PAI‐1	Alpaca	VHH‐2w‐64 (Nb64)	Surface loops around central β‐sheet A	Switches PAI‐1/PA to substrate pathway	Research/Therapy	60, 105
PAI‐1	Alpaca	VHH‐s‐a27	None defined	Neutralization of PAI‐1 function	Research	105
PAI‐1	Alpaca	VHH‐s‐a93	Vicinity of reactive center loop	Interferes with initial PAI‐1/PA complex formation	Research	105
PAI‐1	Alpaca	VHH‐2g‐42 (Nb42)	Vicinity of reactive center loop	Interferes with initial PAI‐1/PA complex formation	Research/Therapy	60, 105
PN‐1	Synthetic library	KB‐PN1‐A08, ‐B11, ‐F06, ‐H12	Reactive center loop	Neutralization of human and murine PN‐1 function	Research	106
hTAFI	Alpaca	VHH‐TAFI‐i and VHH‐TAFI‐a series	None defined	Interfere with TAFI activation and/or activity	Research	54, 55, 57
hTAFI	Alpaca	VHH‐TAFI‐a51 VHH‐TAFI‐i103	None defined	Stimulate activity of TAFI zymogen	Research	56
mTAFI	Alpaca	VHH‐TAFI‐i49	Lys212 & Arg227	Stimulates activity of TAFI zymogen	Research	107
u‐PA	Alpaca	Nb4	Active site	Inhibits u‐PA activity	Research	59
u‐PA	Alpaca	Nb7	37s and 70s loops of the N‐terminal β‐barrel	Allosteric inhibitor of u‐PA activity	Research	58
u‐PA	Alpaca	Nb22	Active site	Inhibits u‐PA activity	Research	58
VWF	Llama	ALX‐0081 (caplacizumab)	Human A1 domain	Inhibition of VWF/glycoprotein Ibα interaction	Therapy	80, 82, 83
VWF	Llama	KB‐VWF‐006bv	Human/murine A1 domain	Inhibition of VWF/glycoprotein Ibα interaction	Research	63, 64
VWF	Llama	AU‐VWFa‐11	Human/murine A1 domain	Specifically detects platelet‐binding VWF conformation	Diagnostics	66, 67, 69, 72, 73, 74

Abbreviations: hTAFI, thrombin‐activatable fibrinolysis inhibitor; mTAFI, murine thrombin‐activatable fibrinolysis inhibitor; PA, plasminogen activator; PAI‐1, plasminogen activator inhibitor‐1; PN‐1, protease nexin‐1; u‐PA, urokinase plasminogen activator; TAFI, thrombin‐activatable fibrinolysis inhibitor; VWF, von Willebrand factor.